Revolvers have changed very little in their overall design and operation in over 100 years, and are generally comprised of a frame, a cylinder, a firing mechanism and a barrel. As is known in the art, revolvers begin as metal blanks that are forged into close approximations of these major parts. After annealing or heat-treating the parts, they undergo basic machining processes such as milling, drilling and tapping. This manufacturing and assembly process is often relatively costly and can require a great deal of hand fitting to orient and align the various metal components with one another so that smooth operation and firing is achieved.
As alluded to above, a revolver is essentially comprised of four main components: a frame, a cylinder, a firing mechanism and a barrel. The frame generally includes one or more frame portions, often a main frame portion, a hand grip portion, and a trigger guard. The cylinder is mounted on the frame by a yoke and fits within a window in the frame. The cylinder has formed therein a plurality of chambers for receiving cartridges. As the trigger is pulled, the cylinder rotates in the frame to successively present the chambers to the barrel for firing. The cylinder also includes an ejector mechanism for removing cartridge casings subsequent to firing, and a cylinder retaining mechanism for holding the cylinder in place within the window in the frame during operation. Often, a cylinder release bar that can be moved via a thumb piece is provided to actuate the retaining mechanism and thereby allow the cylinder and yoke to be rotated away from the frame and into the cylinder-open position.
The firing mechanism of a conventional revolver includes a trigger, a sear, a hammer, a main spring and a pawl that is sometimes referred to as a “hand.” When the revolver is in an operable mode, pulling the trigger causes the hand to move forward, reciprocate up and engage the ratchet, thereby rotating the ratchet and attached cylinder. However, this particular configuration requires that a slot be cut in the face of the frame in the breech face area to allow for the hand to move from the inner portion of the frame to engage the ratchet and turn the cylinder. Such a configuration results in increased manufacturing time and cost and requires that such components be hand fit precisely so that the revolver may operate smoothly.
Pulling the trigger also causes the sear and hammer to rotate away from the cylinder. The rotation away from the cylinder is resisted by the main spring. After a predetermined amount of travel, the sear and hammer disengage from the trigger and allow the spring to force the hammer toward the cylinder. The hammer is aligned with one of the cylinder chambers and the cylinder chamber, in turn, is aligned with the barrel. A firing pin on the hammer is positioned to strike the cartridge disposed in the chamber.
There is also an interest in designing firearms so that the inner parts of the revolver may be cleaned, serviced, repaired, etc. One solution to this problem is to provide a side plate on the side of the revolver that is pinned or otherwise secured to the frame of the revolver. The removal of the side plate allows access to the internal components of the revolver such as the hammer, sear, firing mechanism and hand. One drawback with the use of a side plate, however, is that the side plate can make the revolver less rigid and induces a series of a-symmetric stresses in the frame which can cause the frame to fatigue and ultimately fail over time. It is therefore a general object of the present invention to provide a revolver that is designed so as to allow access to the interior components while maintaining the structural rigidity of the frame.
A retaining mechanism is necessary to retain the cylinder within the rectangular aperture, especially subsequent to firing. Many prior art revolvers lock the yoke directly into the frame via known means. Other revolvers use a ball detent to restrain the forward end of the cylinder. Often times, however, when a round is discharged, the forces which propel the round down the length of the barrel exert a corresponding force in the opposite direction, that is, towards the rear, handgrip portion of the revolver. Although the effect of this opposite force is marginal on the interconnected elements of the revolver, the manufacturing tolerances inherent in the revolver permit a minute amount of structural translation to occur as a result of this incident and opposite discharge force. The effect of the structural translation of certain elements in the revolver may cause the cylinder and yoke assembly to move slightly rearwards, causing, e.g., a ball detent to disengage, thus facilitating the unintended pivoting of the cylinder from its closed position to its open position. In such a situation, the revolver must then be clicked back into its cylinder-closed position before additional firing. It is therefore a general object of the present invention to provide an improved cylinder retaining mechanism that will retain the cylinder within the frame during firing.